The 10-Year Secret: How 'The Abyss' Was Planned Since Day One of Stranger Things

The new batch of Stranger Things Season 5 episodes has delivered one of the most critical pieces of the puzzle that has haunted Hawkins for a decade. If you thought the Upside Down was the source of all evil, you were mistaken. Episodes 5 through 7 officially introduced “The Abyss,” the true home of the shadows, revealing that the Duffer Brothers have kept this secret locked away since their very first meeting with Netflix.

The Abyss vs. The Upside Down

The geographical distinction has finally been clarified through Dustin Henderson’s deductions. The place where Vecna (Henry Creel) resides with the captured children—that rocky, stormy, alien desert seen in glimpses over past seasons—is not the Upside Down. This hostile environment is The Abyss.

According to the newly presented mythology, the Upside Down (the frozen copy of Hawkins) functions merely as a “bridge” or tunnel between our reality and The Abyss. It was Eleven who inadvertently created this connection when she banished Henry, pushing him through the void until he landed in this original dimension of monsters.

The 20-Page Document and “Dimension X”

What is most impressive is that this complex cosmology wasn’t written just now. Matt Duffer revealed to Variety that, back during the production of Season 1, Netflix demanded a logical explanation for the supernatural elements. “We were very emphatic that we didn’t want to explain everything in the show to keep the mystery, but they said, ‘Okay, but we would like to know,'” Matt recounted. The result was a 20-page mythology document that served as the bible for the entire series.

In that original document, The Abyss went by another name: Dimension X. The nomenclature was a direct reference to Teenage Mutant Ninja Turtles, a favorite 80s cartoon of the creators, where the villain Krang inhabited a dimension of constant war. Although the series opted for the name “The Abyss” (a reference more aligned with D&D), the concept has remained unchanged for ten years.

With the stage set and the geography of the apocalypse finally mapped out, the core group of Hawkins heroes prepares to invade The Abyss in the final episode, which promises to be a cinematic event on December 31st.